Help identifying nutrient problem

Nabbers

Nabbers

Well-Known Member
I have two plants (Great White Shark) in week 3 of flowering on a hydroponic dutch bucket system. PH of the nutrient solution is 6, sometimes drops to 5.7 and I check it regularly. I'm using 12g 4-18-38 + micronutrients with 12g Calcium Nitrate and 6g Epsom Salts and a half scoop of Great White Myco in 5 gal RO water, PH adjusted and then adding 50ml of CES Sour Dee 0-0-2 for carbs.

These plants look great at the tops but at the bottom they are still producing some new leaves where they were lollipopped and the new growth is all pretty yellow. Over the past week, some of the biggest leaves have started to turn yellow and fall off. Every day I seem to pick up a leaf or two off the bottom of the tent or find one dangling in the branches. There's some browning along the edges and tips of a few leaves here and there.
Nice Looking Tops:
20160615_103338.jpg 20160615_103631.jpg
Yellowing New Growth:
20160615_103438.jpg 20160615_103016.jpg
Browning and spots on older leaves:
20160615_103050.jpg 20160615_103537.jpg
 
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Nabbers

Nabbers

Well-Known Member
That was my first thought, but I'm a bit confused by it - I thought that usually happened during veg? I'm giving as much nitrogen now in flower as I did through all of veg and it didn't show up until now. Since I still have a few weeks left of flower, should I bump up the nitrogen or just let it drop off as it gets closer to harvest time?
 
Bugeye

Bugeye

Well-Known Member
4-18-38 isn't ideal for veg so you went into flower already low on N. I would bump up N a bit.
 
Nabbers

Nabbers

Well-Known Member
I add equal amounts of calcium nitrate with the 4-18-38. It comes out equalling 20-18-38.
 
SPLFreak808

SPLFreak808

Well-Known Member
Nabbers said:
I have two plants (Great White Shark) in week 3 of flowering on a hydroponic dutch bucket system. PH of the nutrient solution is 6, sometimes drops to 5.7 and I check it regularly. I'm using 12g 4-18-38 + micronutrients with 12g Calcium Nitrate and 6g Epsom Salts and a half scoop of Great White Myco in 5 gal RO water, PH adjusted and then adding 50ml of CES Sour Dee 0-0-2 for carbs.

These plants look great at the tops but at the bottom they are still producing some new leaves where they were lollipopped and the new growth is all pretty yellow. Over the past week, some of the biggest leaves have started to turn yellow and fall off. Every day I seem to pick up a leaf or two off the bottom of the tent or find one dangling in the branches. There's some browning along the edges and tips of a few leaves here and there.
Nice Looking Tops:
View attachment 3708425 View attachment 3708431
Yellowing New Growth:
View attachment 3708426 View attachment 3708430
Browning and spots on older leaves:
View attachment 3708428 View attachment 3708429
Click to expand...
I think its just a bad ratio too much p/k or not enough N can cause this, why so much K? K can fuck shit up too. Also,the first two weeks of flower should be getting plenty of N to prevent pre-mature yellowing just as bug is saying, you cant really give enough N during flower with a 1-1-2 ratio, not unless you find a cut that seems to not mind it.
Screenshot_2016-06-15-10-25-56.png
 
Nabbers

Nabbers

Well-Known Member
Oh, well I'll bump up the N, then. I'd read everywhere that they needed less N in flowering, so I thought what I had would be more than necessary. As far as the K, I've been using a tomato ratio from Masterblend and throughout veg they've loved it. I didn't realize I needed to go all the way to 3-1-2 most of the veg stage and have been sticking near that 1-1-2 the entire grow. So if I just add more Cal-Ni 15.5-0-0 to my blend I should be able to get to a 3-1-2 pretty easy during veg, right?
 
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SPLFreak808

SPLFreak808

Well-Known Member
Nabbers said:
Oh, well I'll bump up the N, then. I'd read everywhere that they needed less N in flowering, so I thought what I had would be more than necessary. As far as the K, I've been using a tomato ratio from Masterblend and throughout veg they've loved it. I know a lot of people have said they've had great results with Jack's Hydroponic which is 5-12-26, which also gets mixed with Cal-Ni and comes out to a pretty similar ratio - less K but still quite a bit. I'm trying to put together a proper ratio from dry mix fertilizers - I'm just not interested in dropping huge amounts of cash on ten different bottles of liquid nutes that will barely last a single grow. Maybe I'll just switch to Jack's and see if the ratio works better.
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You can use less N in flower if you feed high N in veg/early flower. Thats how most people get away with it however its so much easier to just use 1-1-1 or 2-1-1 all the way, it minimizes chances of primary deficiencies which is what new growers want
 
Nabbers

Nabbers

Well-Known Member
So at this point, should I change my mix completely, or just bump up the N until they recover? I'm thinking about ordering the Dyna-Gro Foliage 9-3-6 and Bloom 3-12-6 and some CaliMagic for the next grow. I could get one of those right now if it would save the day.
 
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SPLFreak808

SPLFreak808

Well-Known Member
Nabbers said:
So at this point, should I change my mix completely, or just bump up the N until they recover? I'm thinking about ordering the Dyna-Gro Foliage 9-3-6 and Bloom 3-12-6 and some CaliMagic for the next grow. I could get one of those right now if it would save the day.
Click to expand...
Well yeah that would work, you'll hardly ever use the 3-12-6 unless you like yellow plants lol
 
SPLFreak808

SPLFreak808

Well-Known Member
Nabbers said:
So then... switch to the 9-3-6 plus Cal-Mag right now and ride it out until the flush?
Click to expand...
Foliage pro and cal/mag is pretty simple and most of the time foliage pro alone is sufficient if you use good tap water. Strains that hog calcium might show if you use r/o or crap tap so its good to have cal/mag on hand. Try to simplify everything that way you will have an easier time learning what plants want.
 
Nabbers

Nabbers

Well-Known Member
Without giving too much away, I live in an area that very regularly makes the national list of worst tap water - what comes out of my tap is visually chunky and I have to use a filter built into my shower head or I'll itch all day. I have a 5gal jug that I take to grocery stores and refill from their RO systems for 40c per gal, and even then I get a pH reading below 5 on my frequently calibrated digital meter. So I'm thinking pH adjusters on RO with CalMag is the way to go for water. I'll give that Foliage pro a try. They sure were healthy looking up until now, though.
 
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